Adding custom API certificates to OpenShift Container Platform 4 during installation

Issue

• Currently we have to replace the API Server certificates after the cluster install finished, using Adding API server certificates. It would simplify the installation process if the custom API Server certificates could be supplied to the installer an would be directly be in place after the cluster install process finished. Even if this can be considered a post-installation task it requires some additional effort to make things work, which is why it would be nice to have the certificates configured right at installation time.